It is already known to use vehicle sensors, such as acceleration sensors, to detect a crash by comparing sensor signals from these acceleration sensors to predefined threshold values. Furthermore, it is known to use vehicle sensors for occupant categorization in the manner of a seat mat in a vehicle seat.
German Published Patent Application No. 197 40 020 describes a device for activating an airbag system in a motor vehicle, which activates the restraining means as a function of the impact situation or the impact intensity and the occupant position. In German Published Patent Application No. 196 10 833, it is stated that the impact velocity determines the gas quantity used to inflate an airbag.
From PCT Publication No. 99/03711 it is known to take the weight of a vehicle occupant into account in the deployment of restraining means in a collision. From German Published Patent Application No. 197 40 020 it is known to activate an airbag as a function of instantaneous data from the impact-detection device and/or of instantaneous data of a device for occupant or object detection. From PCT Publication No. 97/21566, it is known to protect a vehicle occupant individually from the effects of a traffic accident. In this case, the instantaneous circumstances of the crash situation are taken into account, especially those parameters that determine the individual kinetic energy of the vehicle occupant.